We have scheduled a shut down of cleanroom operations for 48 hours to complete a 6 month preventive maintenance procedure. We plan to shutdown cleanroom operations on Tuesday (1-May-07) at 7:00 AM and plan to be completed by Wednesday (2-May-07) at 5:00 PM. Maintenance is required for our cleanroom makeup air handlers and chemical exhaust units. We will also complete cleanroom troubleshooting to improve temperature repeatability during this time. Thank you for your understanding and patience during this necessary procedure. If you have any questions or concerns please contact me. Regards, Mark Voorhis Building Manager Purdue University Birck Nanotechnology Center Ph: 765-494-3036